1. Field of the Invention
The present invention relates to a liquid crystal panel of a liquid crystal display device, and particularly to a liquid crystal panel configured to efficiently utilize light provided thereto.
2. General Background
A liquid crystal panel of a liquid crystal display device does not provide its own illumination. Therefore an artificial light source is provided with a liquid crystal panel, or the liquid crystal panel relies on ambient light. The artificial light source is typically a backlight module, which provides light beams having a desired brightness and uniform distribution.
Referring to FIG. 16, an exploded, side cross-sectional view of a conventional liquid crystal display device is shown. The liquid crystal display device 1 includes a liquid crystal panel 4 and a backlight module 5. The backlight module 5 is aligned with the liquid crystal panel 4 to uniformly illuminate the liquid crystal panel 4.
The liquid crystal panel 5 includes a pair of substrates, such as an upper glass substrate 11 and a lower glass substrate 13 located opposite to the upper glass substrate 11. A liquid crystal layer 12 is disposed between the substrates 11 and 13. A color filter layer 15 and a black matrix layer 14 are individually formed on an inner side of the upper glass substrate 11. A plurality of metal lines 134 are formed on an inner side of the lower glass substrate 13.
Referring also to FIG. 17, this is an enlarged, top plan view of part of the color filter layer 15 and the black matrix layer 14 of the liquid crystal display device 1. The color filter layer 15 includes a plurality of red color filter units (R) 151, a plurality of green color filter units (G) 152, and a plurality of blue color filter units (B) 153. The black matrix layer 14 includes a plurality of black matrix units 140 that fill spaces between the red color filter units (R) 151, the green color filter units (G) 152, and the blue color filter units (B) 153. A material of the black matrix layer 14 is a non-transparent resin. Thereby, light leakage is avoided, and a contrast of the liquid crystal display device 1 is enhanced. Thus the purity of colors displayed by the liquid crystal display device 1 can be enhanced.
The backlight module 5 normally includes a light source 16, a light guide plate 17, and a reflective sheet 18. The light source 16 emits light beams to the light guide plate 17. The light beams transmit and reflect inside the light guide plate 17, and light beams that escape from a bottom of the light guide plate 17 are reflected by the reflective sheet 18 back into the light guide plate 17. Overall, a top surface of the light guide plate 17 provides planer light beams to the liquid crystal panel 4. In general, the light beams directly transmit through the lower glass substrate 13, the liquid crystal layer 12, the color filter layer 15, and the upper glass substrate 11. However, a portion of light beams are shielded by the black matrix layer 14. This can result in the liquid crystal display device 1 having a low brightness and a low light utilization ratio. Hence, there is a need for a liquid crystal panel and a corresponding liquid crystal display device which can overcome the above-mentioned problems.